PRESBYOPIA

Even if you’ve had perfect vision your whole life, there is no escaping presbyopia. Worldwide, about 1.7 billion people in the world have presbyopia1 and, according to the U.S. Census Bureau, 51% of the U.S. population is presbyopic. Eventually, everyone gets presbyopia. Presbyopia is a natural effect of aging that most people start to notice at around age 40. It occurs as the crystalline lens naturally stiffens and is unable to change shape to help the eye focus at near distances. As a result, reading and other near tasks can become challenging. The condition continues to progress as you age, until it finally stabilizes at around age 60.

WHAT CAUSES PRESBYOPIA?

The symptoms of presbyopia can be easily mistaken for hyperopia, or farsightedness, since both make it hard to see objections up close. But the causes for the two conditions are quite different. Hyperopia results when you have a misshaped eye, causing light to focus on the wrong part of your retina. Presbyopia, on the other hand, has nothing to do with the shape of your eye. Presbyopia is caused by a gradual thickening, and loss of flexibility of the natural focusing lens inside your eye. When we’re young, our lenses are soft and flexible. As we age, the proteins in the lens of our eyes slowly change, making them harder. This loss in elasticity makes it more difficult to switch focus and see near objects with the same clarity we once did.

HOW IS PRESBYOPIA DIAGNOSED?

Presbyopia is not difficult for your doctor to diagnose. If you have it, the condition will most likely be easily uncovered as part of your routine comprehensive eye examination. Your doctor will likely perform a standard vision test using the same usual equipment to measure the degree of presbyopia that you have. Once you turn 40, more frequent eye exams are recommended. Some signs that you can look for yourself, which can signal a need to ask your doctor about presbyopia include:

Difficulty reading small print
Blurry near vision and problems seeing objects up close
Needing to hold reading material farther than arm’s distance in order for it to come into focus.
Headaches
Eyestrain
Feeling tired when performing near activities

If you are experiencing any of these symptoms, it is likely that treatment or a new prescription is needed.

PRESBYOPIA TREATMENTS

There are several ways to deal with the effects of presbyopia, including glasses, contact lenses and surgery. If you don’t need prescription lenses for distance vision, a pair or reading glasses can help you get by when performing near tasks. If, however, you already wear glasses, switching between two pairs can be cumbersome. If you wish to remain in glasses, consider a progressive lens so you can use the same pair of glasses for near and far activities. Surgical options to treat presbyopia also are available. For example, conductive keratoplasty (CK) uses radio waves to improve near vision. However, the correction is temporary and diminishes over time. More recently, the Kamra inlay was approved by the FDA for treating presbyopia. This implant works by controlling the amount of light that enters your eye. Some people also undergo LASIK for presbyopia. The procedure is not yet approved for creating multifocal zones, so instead surgeons correct one eye to see near objects and the other to see well at distance. This is called monovision. Contact lenses are a third option for presbyopia. These lenses are available with multifocal properties to help you see clearly at all distances. Alternatively, you can use contact lenses to achieve monovision, but studies show that patients usually prefer multifocal contact lenses for most activities.2 Many soft contact lens options are available for presbyopes, but some people struggle with these lenses due to movement of the lenses creating visual instability. Another challenge with soft contacts are that people who have presbyopia tend to struggle with age-related dry eye, which can make it difficult for them to comfortably wear contact lenses.

SCLERAL LENSES FOR PRESBYOPIA

Doctors often recommend a gas permeable lens when a patient has presbyopia and another condition like dry eye or astigmatism. Gas permeable lenses offer outstanding optics, which are often needed with the visual age-related challenges that presbyopia can bring. Scleral lenses, in particular, are a relatively new type of lens that can be very successful in patients who have presbyopia. A scleral lens is a large-diameter contact lens that vaults across the entire corneal surface and rests on the white part of the eye, known as the sclera. Liquid fills the space between your eye and the back surface of the scleral lens. This liquid layer helps smooth out defects caused by dry eyes and astigmatism and provides a more uniform refractive surface. It also continuously bathes your corneal tissue, which can be a big benefit as eyes dry with age. These lenses are very stable in position on the eye, so it can provide more stable vision for presbyopia. If you have presbyopia, talk to your eye doctor to learn about new treatments that can keep you feeling young as your eyes age.

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